I don’t have strong feelings about vaccinations. My disdain for the smug hubris of the Smart People makes me sympathetic to accusations that they understate the risks, and I do find the alleged huge increase in recommended vaccines a little unsettling. Yet my desire to be reasonable and moderate innoculates me against much of the hysteria, and I am not convinced there is non-cherry-picked causation for the recent increases in autism diagnoses, especially because as far as I understand the whole thing was literally started by a guy who was paid by lawyers to make it up so they could do lawsuits about it.

I generally stay out of the fray due to my lack of knowledge, but the other day I came across a particularly poor anti-anti-vaccination piece that displayed the very logical fallacies it attributed to its opponents, and I couldn’t help but comment. Julia Ioffe, writing in the New Republic, indignantly describes her excruciating experience with pertussis (a.k.a. “whooping cough”), blaming it all on the rising crop of folks who refuse to vaccinate their children against such things.

If you don’t think very hard, her accusation makes sense. “Since the introduction of a pertussis vaccine in 1940,” the disease “has been conquered in the developed world… Until, that is, the anti-vaccination movement really got going in the last few years.” Now cases are on the rise again!

For herd immunity to work, 95 percent of the population needs to be immunized. But the anti-vaccinators have done a good job undermining it. In 2010, for example, only 91 percent of California kindergarteners were up to date on their shots. Unsurprisingly, California had a massive pertussis outbreak.

Oh no! The anti-vaxxers are ruining the herd immunity that has kept us safe since the 1940′s! Now she has the whooping cough; “thanks a lot, anti-vaccine parents.”

But hold on just a minute. It doesn’t surprise me that places “with high concentrations of conscientious objectors” seem more likely to have outbreaks; the un-vaccinated are more likely to get the disease. But does it follow that those un-vaccinated children are also more likely to give that disease to adults like Julia Ioffe?

I don’t think it does. Other journalists have politely pointed out some logistical and technical reasons these children probably aren’t to blame. But the above link doesn’t highlight the fundamental logical flaw in Julia’s accusation that made me suspect she was wrong all along.

Julia asserts that un-vaccinated children are destroying herd immunity. This may be true, but if you’re not careful you’ll think she’s implying that this destroys immunity for everyone – as if 95% of us have been working hard to hold up this giant edifice but now that these 5% are walking way it’s coming crashing down on all of us!

Remember, herd immunity is how the vaccinated protect the small percentage who can’t be vaccinated because they’re too young or weak or whatever. If fewer people are vaccinated, it may make an outbreak more likely, and it may hurt the ones who can’t be vaccinated. But – unless I’m missing something here – it should have no effect on the 90% are still immune!

Is Julia really implying that un-vaccinated children somehow destroyed her own immunity? Of course not. She freely confesses that she was not immune: “I was vaccinated against pertussis as a child, but the vaccine wears off by adulthood, which, until recently, was rarely a problem because the disease wasn’t running rampant because of people not vaccinating their kids.”

But this makes no sense. Julia has subtly switched from claiming that the majority of the population was protecting a minority to claiming that a minority of children are no longer protecting the majority of adults. The only way to salvage her accusation that these kids gave her whooping cough is to imply that adults like her are both immune (contributing to herd immunity) and not immune (getting the disease) at the same time! But if most adults like her aren’t immune, then there wasn’t any herd immunity in the first place.

If, say, 80% of the population is walking around with worn-off pertussis vaccines, having no immunity to the disease, and some of the 20% who are children stop getting the vaccine, it makes sense that there might be marginally more favorable conditions for more outbreaks, especially if children tend to congregate more in schools and the like. But what right does one not-immune person have to criticize another not-immune person, just because they more recently joined the pack? That’s like blaming your apartment eviction on your roommate because he just stopped paying the rent, even though you haven’t been paying it for years!

A slight decrease in children getting the vaccine can only mean a very slight increase in the total non-immune population, which apparently was probably already a vast majority! How does she know that a small percentage of non-immune children are so much more to blame than the vast majority of non-immune adults all around her?

The only thing left to support Julia’s accusation is that the general resurgence in whooping cough outbreaks seems to correlate with the recent increase in the anti-vaccination movement. But now we’re back to the very correlation-causation fallacy that the anti-vaccination movement is accused of falling for in the first place. It must simply be natural to look for someone to blame, and whether it’s autism or pertussis, the attraction of the fallacy seems to play no favorites.

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13 Responses to The Logical Fallacies of Blaming Anti-Vaxxers For Your Whooping Cough

But my understanding of the way inoculations work is that they work CUMULATIVELY. You don’t achieve 100% immunity to disease-X just by getting shot-X; you maybe get 20%. That is, you lower your odds of contacting the bug by 20%. So if 4 people you know have it, you won’t get it until you run into a 5th. If one of them instead gets the shot too then your odds improve even more. That’s how I understand it anyways.

I am fairly certain this is completely wrong. Herd immunity relies on nearly 100% of people to be 100% immune. As the theory goes, when this occurs the disease will have no ability to spread and will not be able to reach the small percent who aren’t vaccinated.

I think my example confused you because I used such a low number for a vaccines effectiveness… in reality, vaccines are 80%+ effective. But no vaccine is 100% effective.

Thus, herd immunity isn’t only about the non immunized, it’s also about reducing the slim odds that an immunized person can still get sick.

In other words, it is in fact cumulative, but the baseline starts at 80-90% rather than 20%. I probably should have started with a more realistic figure but was just trying to paint the idea.

Anyways, though I vaccinate for most things and I believe in vaccination generally, I think it’s a terrible thing that our s society is starting to demand sacrificing the individual to the will of the group. As if the only thing of value in life is breathing.

I am allergic to several vaccines, pertussis among them. Because my reactions to the first shots contraindicated me ever getting the vaccines again, I was never made fully immune, and I couldn’t get a booster as an adult. Whooping cough was the most horrible experience of my life and I’ve birthed 3 children drug-free. Get vaccinated. Period.

No no no. Herd immunity is what protects the herd, the vaccinated and the unvaccinated. 95% is the generally accepted safe level of compliance. There are failures, not just noncompliance, that threatens the vaccine success. When compliance dips too low, outbreaks happen. These outbreaks are the fault of kooks. In fact, if it werent for noncompliance, more diseases would be eradicated. So thats how it would be the parents fault.

Wouldn’t this only be true if the failure rate is very small? If the vaccine is failing or wearing off for more than 5% of the population, then there isn’t any herd immunity to begin with, so how are additional children who fail to be vaccinated any more to blame for an outbreak than additional adults who fail to get boosters?

I just learned this in my advanced biology class from a former lab scientist, turned biology teacher. He said that vaccines don’t work 100%. If you remember how vaccines work, it’s not immunity, per se, but instead your body reacting MUCH faster to the pathogen and destroying it before it can do too much harm. He explained that if you are bombarded too often with the disease, no amount of vaccine can help. Also know that anything below a pathogen’s median infective dose (or ID50, the amount needed to infect 50% of a population) is generally harmless to a person. If I get one bacteria of a disease that has an ID50 of 500, then I’m probably not going to get infected. You can think about vaccines as rather raising the ID50 required to infect an individual. So herd immunity IS TRUE.

Also the fallacy that was stated in the article which says that if a few more are not immune, then there should be only a few more infected is outrageous. It increases exponentially.

And one last thing; a not-immune individual who has gotten immunized but hasn’t gotten a booster recently has much more merit than someone who is too selfish to get vaccinated to protect others. At least that other person tried, and is still somewhat immunized. Any immunization is much better than none (like in your food article. some exercise is much better than none).

Are you kidding? “Too selfish”? Since when do I have to sacrifice my child’s health and well being by injecting them with formaldehyde and acetone, to “protect” other people’s kids? My job as a parent is to protect MY CHILD. I’m not God, here to sacrifice my son for the welfare of mankind. I’ll be damned if I’m going to be forced into injecting my son with known neurotoxins on the off chance it might help him and possibly help another. Vaccines are made with toxins, known neurotoxins, chemicals. Any little bit of good they MIGHT do isn’t worth injecting that into a child’s fragile
Immune system. Over my dead body will I ever vaccinate my children.

Scientific examination of what is contained in vaccines is often left out of the discussions of ‘to vaccinate or not’…though it is the most important. How anyone can trust this failing government to protect its citizens over their need for funds has their head in the sand! The US is a Fascist state, corporations run the government, corporations are there to make money…for themselves and to pay-off the politicians. Yeah…think I will pass on that fast-track, mega-bucks Big Pharma funding Ebola vaccine and any others until it’s not a choice anymore. Then I will detox to the best of my ability and curse of what has become of the nation I once loved and its citizens that let it all fade away.

I just read your whooping cough post in preparation for one I will be writing on anti-vaccers and the I’m-outraged-about-anti-vaccers. Good stuff here. Anyway, you may be interested in a related post about Disney Fingerprint scanners – Do you really want to touch it? Just see the 2 Disney posts on http://itbegsthequestion.com/
Anyway, I agree that there are a lot of misconceptions surrounding the “Vaccer” issue. And imho a lot of folks want to run headlong toward a slippery slope. Good post.